EXCITATION KINETIC IN AN ARGON PLASMA-COLUMN PRODUCED BY A SURFACE-WAVE AT ATMOSPHERIC-PRESSURE

The excitation kinetic of a surface wave plasma produced by microwave is not well-known. This work presents an experimental study of this ki netic in Ar plasma. The 4p, 5p and higher levels of the Ar atomic syst em have been studied to determine their equilibrium separation. 5p and higher levels were found that followed an equilibrium distribution bu t the 4p levels were underpopulated in respect to this ditribution. Th en the plasma is a recombining plasma which is in partial local thermo dynamic equilibrium (pLTE). Using the phase diagram that is divided in different areas by the Green and Byron criterium we have established that the 4p levels are in saturation zone and the 5p levels and higher ones are in pLTE. For our discharge positions; those nearest to the e xcitator are the nearest to equilibrium population, because higher ele ctron temperature and density imply that the plasma is nearer to therm odynamic equilibrium.